Interchangeable tooth



R. l. McVlCKER.

4INTERCHANGEABLE T OOTH. APPLICATION HLEDFEB. 21, 1921.

Patented Feb. 21, 1922.

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ROBERT J`. MPVICKER, OF NEW YORK, It'. Y.

INTEBJCHANGEABLE TOOTH.

Moussa. i

Specification or Letters Patent. Patented Feb. 21, 1922.

Application filed February 21, 1921. Serial No. 446,694.

To all whom t may concern Be it known that I, Renner J. MoVrcKnn,citizen of the United States, residing at New York city, in the countyof New York and State of New York, have invented new and usefulImprovements in Interchangeable Teeth, of which the following is aspecification.

This invention relates to interchangeable teeth and one of the principalobjects is to produce a false tooth and backing therefore which shall beso constructed and coact in such manner that if the tooth is chipped orotherwise injured after being placed, it may be readily removed and anew tooth substituted without the necessity of removing the entirebridge or backing.

Another object is to produce a device of this nature which shall besimple of construction, and highly eliicient for the purpose for whichit is'designed.

Another object is to construct a device of this nature which shallobviate the use of pins and other like members, by substituting a tenonwhich tends to strengthen the tooth.

With these and other objects in view which will be more apparent as thespeciication proceeds, the invention resides in certain novelconstruction, the essential elements of which are hereinafter fully described, are particularly pointed out in the appended claims, and areillustrated in the accompanying drawing, in which:

Figure l is a vertical sectional view of the preferred form of tooth andbacking assembled.

Fi ure 2 is a perspective View of a second orm of tooth.

Figure 3 is a vertical sectional view of the tooth shown in Figure etassembled with its backing.

Like characters of reference refer to like parts in all views.

Referring to the drawing in detail, 10 represents an artificial tooth,preferably of porcelain, provided at its rear side with a dovetail tenon11, which extends considerably in rear of the body portion at the neckof the tooth and gradually approaches the body portion into which itfades or blends near the cutting edge. The tenon 11 is also considerablybroader tow-ard the cutting edge than at the neck of the tooth whichpermits its free movement into and out of the backing now to bedescribed.

The backing for the form of tooth above described is shown at 12 and ismade of a thin sheet of gold or other metal 13 which is formed over thedovetail tenon and eX- tends below the tooth or facing 10 to form thecutting edge of the tooth. This sheet after being properly formed to thetooth of facing is then provided with suitable metal or otherreinforcement 14 which is suitably formed for the special needs of theparticular case as is well understood in the art. In this way, thedentist is enabled to form his own backing, it being necessary toprocure only the desired tooth l0 from the manufacturer. Or if desired,the backing can be purchased from the manufacturer. During theapplication of the material 14 the porcelain tooth l0 is of courseremoved. After the bridge 13-14 is set in the mouth of the patient, thetooth 10 is slipped into its seat and cemented there as will beunderstood by those skilled in the art. Should the tooth 10 bethereafter chipped or cracked, it can be readily removed from the bridge13---14L by grinding or in any other desirable manner, and after thedovetail slot in the bridge is cleaned, a new tooth may be substitutedwithout the necessity of removing the bridge.

The flanges of the tenon are formed with a curved undercut at 15, andextend from the neck of the tooth only part way to the cutting edge, sothat shoulders 16 are formed at the sides. The undercut portions 15extend down to form curved seats 17. The backing for this form of toothwill have co-acting shoulders 16 and will have lugs 19 to t into theseats 17. It will be seen that this form is a variation of thepreviously described form and that the tooth may be as readilyinterchanged in this case as in the first form.

While I have described what is deemed to be the most desirableembodiment of my invention, it is obvious that many of the details maybe varied without in any way departing from the spirit of my invention,and I therefore do not limit myself to the exact details of constructionherein set forth nor to anything less than the whole of my inventionlimited only by the appended claims.

What is claimed as new is 1. An interchangeable tooth comprising afacing portion, and a dovetail tenon integral with the rear portion ofthe tooth and having its rear face sloping from the neck of the toothtoward the cutting edge of the tooth and narrower at the neck of thetooth than itis toward the cutting edge thereof, the undercuts of saidtenen being curved and extended to form cup-like seats,

and said tooth beingrpro'vided with shoul-v ders adjacent to said seats.Y

2. In a device of the class described, the combination of a backingprovided with anges extending from the neck toa point Yintermediate theends of the Ybac-king and aforesaid shoulders of said backing.

,Roe-em J. Movielin;

